The invention relates to apparatus for damping fluctuations of torque, and more particularly to improvements in apparatus wherein two rotary bodies can turn relative to each other against the opposition of elastic dampers and/or friction generating devices. Still more particularly, the invention relates to improvements in apparatus which can be utilized in motor vehicles to prevent or oppose fluctuations of torque which is transmitted between the engine and the variable-speed transmission.
It is known to provide the power train of a motor vehicle with a pair of flywheels one of which is driven by the crankshaft of the engine and the other of which can transmit torque to the input shaft of the variable-speed transmission, normally in response to engagement of a friction clutch. Reference may be had to numerous United States patents and pending United States patent applications, as well as to numerous foreign patents, of the assignee. It is also known to provide such power trains with dampers and/or friction generating devices which operate between the flywheels to oppose angular movements of the engine-driven flywheel relative to the other flywheel and/or vice versa. It is further known to provide such apparatus with friction generating devices which are operative while the flywheels are driven at a relatively low speed but cease to oppose, under the action of centrifugal force, angular movements of the flywheels relative to each other when the RPM rises beyond a preselected value.